Compounds of formula 1 and 1-1, wherein R1 is hydrogen, hydroxy, amino or halogen, R2 is hydrogen, hydroxy, or halogen and R3 is hydrogen (Formula 1) or R1 is hydrogen and R2 and R3 taken together with the ethenylene group connecting them form phenyl, pyrrole, pyrroline, oxopyrroline, pyrazole, triazole, or imidazole (Formula 1-1), A is R4 R5 are hydrogen, methyl, ethyl or halogen except that R4 r5 cannot both be hydrogen; and 1) B is hydrogen, or lower alkyl; or 2) B is where R6 R7 R8 and R9 are independently hydrogen, hydroxy, aminosulfonyl, halogen, lower alkoxy, cyano, amino, lower alkyl, lower alkyl amino, or nitro; or 3) B is where R10 is hydrogen, hydroxy, halogen, or lower alkyl and C is a five- or six- membered ring with 0 to 3 heteroatoms which heteroatoms are selected from nitrogen, oxygen, and sulfur, which ring may be unsubstituted or mono- or di- substituted with lower alkyl, cycloalkyl, amino, or substituted amino; 4) B is where X and Y are independently methylene or nitrogen; or 5) B is where at leat one of T, U, V, or W is nitrogen, and any of T, U, V or W which is carbon may be substituted with lower alkyl, lower alkyl amino, lower alkoxy, hydroxy, aminosulfonyl, halogen, cyano, amino, or nitro; or 6) B is where Y is carbon or nitrogen; or 7) B is a five-membered aromatic ring with 1 to 3 heteratoms selected from nitrogen, oxygen, and sulfur which ring may be unsubstituted or mono- or di-substituted with lower alkyl, cycloalky, trifluoroloweralkyl, amino, halogen, substituted amino, or which ring may be fused with a 5 or 6 membered aromatic ring containing 0 to 3 heteroatoms which heteroatoms are selected from nitrogen, oxygen, and sulfur; and pharmaceutically acceptable salts thereof, and related prodrugs, pharmaceutical compositions and methods of treatment, which compounds are useful for treating psoriasis.